Motion guidance device

Abstract

The motion guide device (1) of the present application is provided with an inner ring (10), an outer ring (20), a plurality of rolling elements (30), and a retainer (40, 50) having a plurality of partition walls (41, 51) and a pair of bands (42, 43, 52, 53), as the retainer (40, 50), a radial retainer (40) that retains a plurality of first rolling elements (31) among the plurality of rolling elements (30) and an axial retainer (50) that retains a plurality of second rolling elements (32) among the plurality of rolling elements (30), the pair of bands (52, 53) of the axial retainer (50) is disposed on both sides in the radial direction of the plurality of partition walls (51), and the radial direction dimension of one band (53) is smaller than the radial direction dimension of the other band (52).

Description

Technical Field

[0001] This invention relates to motion guidance devices. This application claims priority based on Japanese Patent Application No. 2024-048206, filed on March 25, 2024, the contents of which are incorporated herein by reference. Background Technology

[0002] Patent Document 1 disclosed below discloses a composite roller type slewing bearing that bears both thrust load and radial load. In this composite roller type slewing bearing, cylindrical rollers for bearing thrust load and cylindrical rollers for bearing radial load, arranged between the inner and outer rings, are respectively held by cages (see reference). Figure 3 ).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 8-105438 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In motion guiding devices like those described above, retainers are used to prevent the rolling elements (cylindrical rollers) from contacting each other and to control their posture. Furthermore, the retainers are bent circumferentially along the orbital path of the rolling elements. Therefore, for ease of forming, a pair of radial retainer bands are arranged alternately in the radial direction. However, the band of the radial retainer positioned on the axial retainer side may interfere with the axial retainer.

[0008] The present invention was made in view of the above-mentioned problems, and its purpose is to avoid interference between the radial retainer and the axial retainer.

[0009] Methods for solving problems

[0010] To address the aforementioned issues, a first aspect of the present invention relates to a motion guiding device comprising: an inner ring; an outer ring; a plurality of rolling elements sandwiched between the inner ring and the outer ring; and a retainer holding the plurality of rolling elements. The retainer includes: a plurality of partition walls disposed between the plurality of rolling elements; and a pair of belts connecting the plurality of partition walls circumferentially. The retainer further includes: a radial retainer holding a plurality of first rolling elements that bear radial loads; and an axial retainer holding a plurality of second rolling elements that bear axial loads. The pair of belts of the axial retainer are disposed on both radially opposite sides of the plurality of partition walls of the axial retainer, and the radial dimension of the belt disposed on the radial retainer side of the pair of belts of the axial retainer is smaller than the radial dimension of the belt disposed on the opposite side of the radial retainer.

[0011] The second aspect of the present invention is based on the motion guiding device of the first aspect, wherein the cross-sectional area of ​​the belt of one side is approximately equal to the cross-sectional area of ​​the belt of the other side.

[0012] The third aspect of the present invention is based on the motion guiding device of the first or second aspect described above, wherein at least one of the plurality of partition walls of the axial retainer has a plurality of protrusions on its end face in the axial direction.

[0013] The fourth aspect of the present invention is based on the motion guiding device of the first or second aspect, wherein the pair of bands of the radial retainer are disposed on both sides of the plurality of partition walls of the radial retainer in the axial direction and are staggered in the radial direction.

[0014] Invention Effects

[0015] According to the present invention, interference between the radial retainer and the axial retainer can be avoided. Attached Figure Description

[0016] Figure 1 This is a perspective view of a motion guiding device according to one embodiment.

[0017] Figure 2 This is an exploded perspective view of a motion guiding device according to one embodiment.

[0018] Figure 3 This is an enlarged cross-sectional view of the main part of the motion guiding device according to one embodiment.

[0019] Figure 4 This is a top view of an axial retainer according to one embodiment.

[0020] Figure 5yes Figure 4 The V-V sectional view shown.

[0021] Figure 6 This is a top view of a radial retainer according to one embodiment.

[0022] Figure 7 yes Figure 6 The sectional view of VII-VII shown.

[0023] Figure 8 This is a diagram illustrating the function of a motion guiding device according to one embodiment. Detailed Implementation

[0024] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0025] Figure 1 This is a perspective view of a motion guiding device 1 according to one embodiment. Figure 2 This is an exploded perspective view of a motion guiding device 1 according to one embodiment.

[0026] like Figure 1 As shown, the motion guiding device 1 includes an inner ring 10 and an outer ring 20. The inner ring 10 and the outer ring 20 are formed into annular shapes with a common central axis O and are combined in a manner that allows them to rotate relative to each other.

[0027] In the following description, the direction in which the central axis O extends is called the axial direction. The direction orthogonal to the direction in which the central axis O extends is called the radial direction. The direction surrounding the central axis O is called the circumferential direction.

[0028] Multiple holes are formed in the inner ring 10 and the outer ring 20 along the axial direction. The inner ring 10 and the outer ring 20 can be installed on an object (not shown). The inner ring 10 is configured to be separable in the axial direction into a first ring member 11 and a second ring member 12. The first ring member 11 and the second ring member 12 are fastened by bolts (not shown) that pass through a portion of the multiple holes.

[0029] like Figure 2 As shown, the motion guiding device 1 includes a plurality of rolling elements 30 sandwiched between the inner ring 10 and the outer ring 20, and radial retainers 40 and axial retainers 50 for holding the plurality of rolling elements 30. The rolling elements 30 are cylindrical rollers. In this embodiment, the plurality of rolling elements 30 are arranged in three rows between the inner ring 10 and the outer ring 20.

[0030] Figure 3 This is an enlarged cross-sectional view of the main part of the motion guide device 1 according to one embodiment.

[0031] like Figure 3As shown, a flange portion 21 protruding radially inward (on the right side of the paper) is provided on the inner wall surface of the outer ring 20. The flange portion 21 is formed in an annular shape.

[0032] A rolling surface 21a of the rolling element 30 is formed on the radially inward (right side of the paper) front end face of the flange portion 21. A rolling surface 12a is formed on the second ring member 12, which is radially spaced from the rolling surface 21a of the flange portion 21. The rolling surface 12a is formed at a position lower than the mating surface 13 of the first ring member 11 and the second ring member 12.

[0033] A plurality of first rolling elements 31 are disposed between rolling surfaces 21a and 12a to bear loads in the radial direction. The rotation axis of the first rolling element 31 extends in the axial direction, and the circumferential surface of the first rolling element 31 rolls circumferentially while contacting at least one of the rolling surfaces 21a and 12a.

[0034] The radial retainer 40 has a plurality of partition walls 41 disposed between a plurality of first rolling elements 31 and a pair of belts 42, 43 connecting the plurality of partition walls 41 in the circumferential direction. The radial retainer 40 prevents the first rolling elements 31 from contacting each other and controls the posture of the first rolling elements 31.

[0035] Furthermore, rolling surfaces 21b of the rolling element 30 are formed on the surfaces of the flange portion 21 facing the axial direction on both sides (the upper and lower sides of the paper). A first opposing flange portion 14 is formed in the first ring member 11, which is spaced apart from the flange portion 21 in the axial direction. A rolling surface 14a is formed in the first opposing flange portion 14, which is spaced apart from the rolling surface 21b of the flange portion 21 in the axial direction.

[0036] A plurality of second rolling elements 32 are disposed between rolling surfaces 21b and 14a to bear axial loads. The rotation axis of the second rolling element 32 extends in the radial direction, and the circumferential surface of the second rolling element 32 rolls circumferentially while contacting at least one of the rolling surfaces 21b and 14a.

[0037] The axial retainer 50 has a plurality of partition walls 51 disposed between a plurality of second rolling elements 32 and a pair of belts 52, 53 connecting the plurality of partition walls 51 in the circumferential direction. The axial retainer 50 prevents the second rolling elements 32 from contacting each other and controls the posture of the second rolling elements 32.

[0038] The second ring member 12 has a second opposing flange portion 15 that is axially spaced apart from the flange portion 21. The second opposing flange portion 15 has a rolling surface 15a that is axially spaced apart from the rolling surface 21b of the flange portion 21. Between the rolling surfaces 21b and 15a, and similarly between the rolling surfaces 21b and 14a, a plurality of second rolling elements 32 are arranged, which are held by the axial retainer 50 and bear the load in the axial direction.

[0039] Figure 4 This is a top view of the axial retainer 50 according to one embodiment. Figure 5 yes Figure 4 The V-V sectional view shown.

[0040] like Figure 4 As shown, the axial retainer 50 is formed by connecting arc-shaped retainer members 50a into a ring shape. The retainer members 50a are, for example, resin-molded parts.

[0041] The axial retaining members 50 have straps 52 and 53 arranged on both sides of the plurality of partition walls 51 in the radial direction. Additionally, as... Figure 5 As shown, the bands 52 and 53 are arranged approximately symmetrically with respect to the center point of the partition wall 51. By arranging the bands 52 and 53 in this way, the forming mold (not shown) of the retainer member 50a can be ejected in the axial direction (up and down on the paper).

[0042] The radial dimension of the band 53, which is located on the side of the radial retainer 40 (right side of the paper), is smaller than the radial dimension of the band 52, which is located on the opposite side of the radial retainer 40 (left side of the paper). Specifically, the radial dimension L21 of the band 53 is about 1 / 2 to 2 / 3 the size of the radial dimension L11 of the band 52.

[0043] On the other hand, the axial dimension L22 of belt 53 is larger than the axial dimension L12 of belt 52. This is to make the cross-sectional area of ​​belt 53 approximately equal to that of belt 52. By making the cross-sectional areas of belts 52 and 53 approximately equal, the strength of belts 52 and 53 is made approximately uniform, eliminating undesirable situations such as only one belt breaking under tensile load. It should be noted that, here, "approximately equal" means that the difference in cross-sectional areas of belts 52 and 53 is within the range of ±5%, preferably ±3%, and more preferably ±1%.

[0044] Multiple protrusions 54 are formed on the end faces of both sides (upper and lower sides on the paper) in the axial direction of the partition wall 51. The protrusions 54 are hemispherical. A pair of protrusions 54 are arranged at intervals in the radial direction. The protrusions 54 make point contact with the rolling surfaces 21b, 14a, and 15a to suppress wear of the axial retainer 50 and heat generation caused by friction. It should be noted that if there is only one protrusion 54, the axial retainer 50 may sometimes be tilted around that protrusion 54. Therefore, two or more protrusions 54 are sufficient.

[0045] Figure 6 This is a plan view of the radial retainer 40 according to one embodiment. Figure 7 yes Figure 6 The sectional view of VII-VII shown.

[0046] like Figure 6 As shown, the radial retainer 40 is formed by connecting arc-shaped retainer members 40a into a ring shape. The retainer members 40a are, for example, resin-molded parts.

[0047] like Figure 7 As shown, the radial retainer 40 has strips 42 and 43 disposed on both sides (upper and lower sides of the paper) of the plurality of partition walls 41 in the axial direction. The strips 42 and 43 are staggered in the radial direction. Specifically, the strip 43 is disposed in the center of the partition wall 41 in the radial direction. In addition, the strip 42 is disposed in the radial direction on the side of the axial retainer 50 of the partition wall 41 (left side of the paper).

[0048] The radial dimension L3 and cross-sectional area of ​​belts 42 and 43 are equal to each other. This ensures that the strength of belts 42 and 43 is uniform. On the other hand, belts 42 and 43 are offset in the radial direction by a dimension L4 that is larger than dimension L3. By arranging belts 42 and 43 in this way, the forming die (not shown) used for holding member 40a can be ejected in the axial direction (up and down on the paper).

[0049] Figure 8 This is a diagram illustrating the function of the motion guidance device 1 according to one embodiment.

[0050] like Figure 8 As shown, according to the above-described forming, the radial retainer 40 is formed such that the bands 42 and 43 are offset from each other in the radial direction. Furthermore, as in this embodiment, when the bands 52 and 53 of the axial retainer 50 are symmetrically arranged with respect to the center point of the partition wall 41, as in this embodiment... Figure 8 As shown by the double-dotted line, if bands 52 and 53 are symmetrical, the axial retainer 50 and the radial retainer 40 may interfere.

[0051] Therefore, in this embodiment, the bands 52 and 53 are designed to be asymmetrical. Consequently, the radial dimension of the band 53 disposed on the radial retainer 40 side is smaller than the radial dimension of the band 52 disposed on the side opposite to the radial retainer 40. Therefore, interference between the axial retainer 50 and the radial retainer 40 can be avoided.

[0052] As described above, the motion guiding device 1 of this embodiment includes an inner ring 10, an outer ring 20, a plurality of rolling elements 30 sandwiched between the inner ring 10 and the outer ring 20, and a retaining member for holding the plurality of rolling elements 30. The retaining member has a plurality of partition walls disposed between the plurality of rolling elements 30 and a pair of belts connecting the plurality of partition walls in the circumferential direction. As the retaining member, it includes a radial retaining member 40 for holding a plurality of first rolling elements 31 that bear radial loads among the plurality of rolling elements 30, and an axial retaining member 50 for holding a plurality of second rolling elements 32 that bear axial loads. The pair of belts 52, 53 of the axial retaining member 50 are disposed on both sides of the plurality of partition walls 51 in the radial direction of the axial retaining member 50, and the radial dimension of the belt 53 disposed on the radial retaining member 40 side of the pair of belts 52, 53 of the axial retaining member 50 is smaller than the radial dimension of the belt 52 disposed on the opposite side of the radial retaining member 40. According to this structure, interference between the radial retaining member 40 and the axial retaining member 50 can be avoided.

[0053] Furthermore, in this embodiment, the cross-sectional area of ​​one strip 53 is approximately equal to the cross-sectional area of ​​the other strip 52. This structure ensures that the strength of strips 52 and 53 is approximately uniform, thus eliminating undesirable situations such as breakage of only one strip when subjected to tensile loads.

[0054] Furthermore, in this embodiment, at least one of the plurality of partition walls 51 of the axial retainer 50 has a plurality of protrusions 54 on its end face in the axial direction. According to this structure, by making point contact between the protrusions 54 and the rolling surfaces 21b, 14a, 15a, wear of the axial retainer 50 and heat generation caused by friction can be suppressed.

[0055] Furthermore, in this embodiment, a pair of bands 42, 43 of the radial retainer 40 are disposed on both sides of the plurality of partition walls 41 of the radial retainer 40 in the axial direction and are staggered in the radial direction. According to this structure, the forming die used in forming the radial retainer 40 can be ejected in the axial direction.

[0056] The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. The shapes, combinations, etc. of the structural components shown in the above embodiments are examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0057] Industrial availability

[0058] According to the present invention, interference between the radial retainer and the axial retainer can be avoided.

[0059] Explanation of reference numerals in the attached figures

[0060] 1. Motion guidance device

[0061] 10 Inner Circle

[0062] 11 First Ring Component

[0063] 12 Second Ring Component

[0064] 12a Rolling surface

[0065] 13. Joint surface

[0066] 14 First Opposite Flange

[0067] 14a Rolling surface

[0068] 15 Second Opposite Flange

[0069] 15a Rolling surface

[0070] 20 Outer ring

[0071] 21. Flange portion

[0072] 21a Rolling surface

[0073] 21b Rolling surface

[0074] 30 Rolling element

[0075] 31 First rolling element

[0076] 32 Second rolling element

[0077] 40 Radial retainer

[0078] 40a Retaining component

[0079] 41. Partition wall

[0080] 42 belts

[0081] 43 belts

[0082] 50 Axial retainer

[0083] 50a Retaining component

[0084] 51. Partition wall

[0085] 52 belts

[0086] 53 belt

[0087] 54. Protrusion

[0088] L3 size

[0089] L4 size

[0090] L11 size

[0091] L12 size

[0092] L21 size

[0093] L22 size

[0094] O is the central axis.

Claims

1. A motion guiding device, comprising: Inner circle; Outer ring; Multiple rolling elements, sandwiched between the inner ring and the outer ring; and A retainer that holds the plurality of rolling elements. The retainer has: Multiple partition walls are disposed between the multiple rolling elements; and A pair of strips that connect the plurality of partition walls in the circumferential direction. As the retaining member, it comprises: A radial retainer that retains a plurality of first rolling elements that bear radial loads; and An axial retainer that holds one or more second rolling elements among the plurality of rolling elements that bear axial loads. The pair of straps of the axial retainer are disposed on both sides of the plurality of partition walls of the axial retainer in the radial direction. Furthermore, the radial dimension of the belt on the radial retainer side of the pair of belts of the axial retainer is smaller than the radial dimension of the belt on the opposite side of the radial retainer.

2. The motion guiding device according to claim 1, wherein, The cross-sectional area of ​​one of the strips is approximately equal to the cross-sectional area of ​​the other strip.

3. The motion guiding device according to claim 1 or 2, wherein, At least one of the plurality of partition walls of the axial retainer has a plurality of protrusions on its end face in the axial direction.

4. The motion guiding device according to claim 1 or 2, wherein, The pair of bands of the radial retainer are disposed on both sides of the plurality of partition walls of the radial retainer in the axial direction and are offset in the radial direction.

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